The present invention relates to a new "stable" gel propellant composition, and, more particularly, to a gel propellant composition which contains from about 5 up to 25 wt. % water and does not ignite until pressurized to a pressure of about 900 psi, but then burns at a flame temperature which is substantially cooler than the flame temperatures of solid and liquid propellants of equivalent charge, e.g., at a flame temperature that can be as low as 2000.degree. K. and even cooler.
Currently available propellants of the type typically used in a primed shell or cartridge for rifle and handgun ammunition, for example, can be characterized as having a relatively low burn rate which is measured in centimeters per second. Burn, i.e., flame, temperatures typically can be as high as 2300.degree. K., but are usually higher in the range of up to 3700.degree. K. Such high temperatures are a significant factor in reducing gun barrel life. In addition, burning propellants now in use can produce varying degrees of smoke, fumes and residue, and they can be a substantial safety hazard if not handled correctly or if they are subjected to accident because they can ignite at atmospheric pressure from external stimuli, such as, for example, from heat, friction and impact. For these reasons they are also vulnerable to hostile projectiles.
The propellant of the present invention is a semi-plastic gel composition based on a solid fine particle high explosive which is admixed with an oxidizer and lower energy fuels and which contains from about 5 up to 25 wt. % water and which will not ignite until subjected to a pressure, e.g., from a primer, a booster, or externally applied pressure (liquid or gas) in a closed chamber, of at least about 900 psi. The gel propellant composition is cooler burning and safer to handle, use, and transport than currently available propellants.